Walking down the street, you notice a pebble.
To most of us, it’s a simple thing. You can pick it up, throw it, rub it against the ground to smooth it out. Beyond that, there isn’t much more to do with it. A pebble seems like a very simple system.
But place that same pebble in the hands of a geologist, and an entirely different world opens up. They can study its mineral composition under a microscope. They can run X-ray diffraction to see its internal structure. They can date it to learn its age, and from that, reconstruct the history of the landscape it came from. They can examine the grain size, the weathering patterns, the stratigraphic context — all of which tell stories of volcanic eruptions, glacial shifts, or ancient seas.
What appears simple to one person is layered with possibility for another.
That is the point: complexity is relative. It is not a fixed property of a thing, but something that emerges in the relationship between the system and the observer — shaped by their experience, knowledge, and tools of perception.
I was reminded of this yesterday while on a podcast with my friends Danny Foley and Les Spellman. We were talking about how this same idea shows up in coaching.
Take video, for example. If I film an athlete sprinting and hand that clip to my sister, she’ll probably give me one or two comments. Maybe, “the knees need to be higher.”
That’s about all she sees.
If I send the same video to Dan Pfaff, I’ll get back a long list of observations. He’ll notice subtleties in coordination, posture, force application, asymmetries — including many things that most people would never even think to look for.
It’s not that Dan is making the movement more complex. He’s just attuned to more of what’s already there. His years of experience let him see patterns and relationships that others miss. The system — the athlete running — hasn’t changed. What changes is the observer, and what they can perceive.
This difference isn’t unique to coaching. It has been studied across many fields.
Psychologists have shown that experts don’t just know more facts — they actually see differently. Chase and Simon’s work on chess players found that novices see isolated pieces, while masters see meaningful patterns. The same is true in sport. A beginner might notice a high knee, while an experienced coach notices the interplay of coordination, posture, and force.
Michael Polanyi once said, “we know more than we can tell.” Expertise lives not just in what we can articulate, but in tacit knowledge — the patterns our eyes and bodies have learned to recognize through years of practice.
Herbert Simon argued that complexity is partly in the eye of the beholder. What looks overwhelming to a novice may look straightforward to someone who has learned to see structure. And from ecological psychology, James Gibson described how perception is not passive — it’s an active process of attunement to affordances, the opportunities for action in a given environment.
All of these perspectives point to the same idea: complexity is not absolute. It’s relative to what we bring to the system — our knowledge, our experience, and our ability to perceive relationships.
So whether it’s a pebble on the street or a video of an athlete sprinting, the lesson is the same. Complexity isn’t fixed in the thing itself. It lives in the relationship between the observer and what is observed.
To my sister, the sprinting video is simple. To Dan, it’s layered and full of nuance. To a passerby, a pebble is nothing more than a small rock. To a geologist, it’s a record of deep time.
The system doesn’t change. What changes is who is looking, and what they are able to see.
That’s why in coaching — as in science — we need to be careful about labeling things as “too complex” or accusing others of overcomplicating. Often, they are simply more attuned. They see more. And with experience, so will we.
Complexity is relative. It grows with us.
